Resonant laser ionization and mass separation of 225Ac
J. D. Johnson, Michael Heines, Frank Bruchertseifer, E. Chevallay, T. E. Cocolios, K. Dockx, Charlotte Duchemin, S. Heinitz, Reinhard Heinke, Sophie Hurier, Laura Lambert, Benji Leenders, Hanna Skliarova, Thierry Storà, W. Wojtaczka
Abstract
[Formula: see text]Ac is a radio-isotope that can be linked to biological vector molecules to treat certain distributed cancers using targeted alpha therapy. However, developing [Formula: see text]Ac-labelled radiopharmaceuticals remains a challenge due to the supply shortage of pure [Formula: see text]Ac itself. Several techniques to obtain pure [Formula: see text]Ac are being investigated, amongst which is the high-energy proton spallation of thorium or uranium combined with resonant laser ionization and mass separation. As a proof-of-principle, we perform off-line resonant ionization mass spectrometry on two samples of [Formula: see text]Ac, each with a known activity, in different chemical environments. We report overall operational collection efficiencies of 10.1(2)% and 9.9(8)% for the cases in which the [Formula: see text]Ac was deposited on a rhenium surface and a ThO[Formula: see text] mimic target matrix respectively. The bottleneck of the technique was the laser ionization efficiency, which was deduced to be 15.1(6)%.